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1.
羊穿衣是一种能有效保护羊体羊毛羊绒的管理方法,它可以调节绒山羊体表的微环境,改善羊毛羊绒的生长条件,减少干旱地区沙尘和粪尿杂质、草屑对羊毛羊绒的污染,降低高山地区强烈紫外线对羊毛羊绒的辐射损伤,以及风霜雨雪对羊毛羊绒的侵蚀,防止羊绒被植被挂脱,从而达到提高羊毛羊绒品质的目的。此项技术是提高羊绒经济效益最简便的方法,其成本低,见效快,经济效益显著(穿羊衣后每只羊可增加纯利润21元)。  相似文献   

2.
根据GenBank登录的鹅细小病毒(GPV)和番鸭细小病毒(MDPV)非结构蛋白(NS)基因特征,本研究设计1对特异性引物对GPV和MDPV基因组DNA进行PCR扩增,目的片段大小均为810 bp,并对PCR产物进行切胶回收。用EcoRⅠ酶对GPV和MDPV特异性胶回收产物进行酶切鉴定,结果显示MDPV经EcoRⅠ酶切后琼脂糖凝胶电泳检测片段为2段,大小为530和280 bp;而GPV经EcoRⅠ酶切后琼脂糖凝胶电泳检测片段大小不变。本研究建立了一种快速区别GPV和MDPV感染的检测方法,可对番鸭感染水禽细小病毒的情况进行快速鉴别诊断。  相似文献   

3.
利用套式PCR扩增在病毒(CAV)687bp片段,分别以HaeⅢ,HinfⅠ和HpaⅡ酶切,通过聚丙烯酰胺凝胶电泳分析其限制性片段长度多态性。用该技术对我国山东分离株的分析表明,SJ1和SJ2与日本的TK5803株和瑞典的1/80和1/91株相同,应属于Tcdd用限制性内切酶酶切图谱多态性(RFLP)分类方法中的第2组。  相似文献   

4.
T-RFLP快速鉴定生鲜肉中牛羊成分的研究   总被引:1,自引:0,他引:1  
试验旨在建立快速检测生鲜肉中牛、羊成分的定性分析方法。通过T-RFLP法,上游引物的5′端用6-FAM进行荧光标记,下游引物5′端用ROX进行荧光标记,PCR结束后选择限制性内切酶HinfⅠ、BlnⅠ进行酶切消化,在测序仪上通过毛细管电泳即可检测荧光标记的两个末端的限制性片段。利用不同物种产生的不同峰谱达到对物种快速定性的目的。该法能够对生鲜肉中牛、羊肉进行定性鉴定分析,不同物种产生不同峰谱,限制性内切酶HinfⅠ酶切牛肉样品所产生的限制性末端片段长度为46和373 bp,限制性内切酶BlnⅠ酶切羊肉样品所产生的限制性末端片段长度为203和515 bp。  相似文献   

5.
为快速确定临床禽腺病毒-Ⅰ群(FAdVs)的血清型,本研究根据FAdVs的Hexon基因设计引物,对12个血清型FAdVs标准毒株进行PCR扩增,并根据扩增目的片段进行酶切位点分析和相应酶切反应研究,建立聚合酶链式反应-限制性片段长度多态性(PCR-RFLP)方法。结果显示,利用该引物可同时扩增12个血清型FAdVs标准毒株,扩增片段大小为894 bp;扩增片段酶切位点分析显示,Eco130 Ⅰ、Pf123Ⅱ、Mlu Ⅰ、Psy Ⅰ和BgⅡ为主要酶切位点,这5种酶切反应结果显示12个血清型FAdVs标准毒株可以得到不同的酶切图谱,且能区分12种血清型FAdVs;应用该酶切方法对本实验室保存的2株已知血清型的分离株进行分析,其结果与已确定的血清型一致。表明本试验建立的PCR-RFLP方法简便、特异性和区分度好,可用于12个血清型FAdVs的分型。  相似文献   

6.
本研究旨在构建高甘氨酸-酪氨酸蛋白(HGTP)启动子荧光素酶报告基因载体并验证其活性,阐明HGTP基因在萨福克羊和中国美利奴羊皮肤毛囊组织中的表达差异与羊毛经济性状的关系。运用PCR方法扩增HGTP基因启动子序列片段,克隆至pGL3-Basic载体中构建重组质粒,并通过双酶切验证和测定核酸序列鉴定;转染皮肤成纤维细胞并检测报告基因的活性;测定羊毛的纤维直径、长度的数据,利用实时荧光定量PCR分析HGTP基因在不同品种绵羊的皮肤毛囊组织中的表达情况。结果显示,萨福克羊与中国美利奴羊的羊毛纤维直径及自然长度差异极显著(P<0.01),HGTP基因表达水平与羊毛纤维直径存在极显著的高度正相关(P<0.01),与羊毛自然长度呈现显著的中等负相关(P<0.05),而羊毛直径与自然长度之间存在极显著的高度负相关(P<0.01)。HGTP基因在萨福克羊和中国美利奴羊皮肤组织中的表达水平差异极显著(P<0.01)。启动子活性荧光素酶检测结果显示,KAP6.1、KAP7和KAP8.1启动子元件在绵羊皮肤成纤维细胞和3T3细胞中均有表达,且在绵羊成纤维细胞中的活性极显著高于在3T3细胞中的活性(P<0.01)。HGTP基因可以作为研究羊毛纤维直径、自然长度的候选基因。构建不同长度的表达载体,转染皮肤成纤维细胞,获得的2个启动子元件都能驱动外源基因在体外细胞水平表达。绵羊HGTP基因启动子的功能研究为调控羊毛发育提供了理论依据。  相似文献   

7.
根据已发表的鹅细不病毒(GPV)核苷酸序列设计并合成了1对引物,对GPV主要结构蛋白VP2和VP3基因进行扩增。所获得的PCR产物与预期片段大小相符,约1.8kb。将该片段直接与真核表达pCR3.1T载体连接,转化人感受态大肠杆菌TOP10F'中增值。在对所提质粒进行快速鉴定、PCR扩增以及BamH I酶切线性化初步鉴定的基础上,经限制性内切酶Sca I 和EcoR V分别酶切进行正反向鉴定,获得了3个正向插入的克隆(PVPA)和2个反向插入的克隆(PVPB)。将正向插入的克隆PVPA1与原核表达载体pET-28b( )分别用BamH I和Xho I双酶切后,回收目的片段进行定向连接,并转化入感受态大肠杆菌DH5a中。对所获得的重组质粒分别经Sca I、EcoR V、BamH I/Xho I酶切,证实含有目的基因,且基因插入方向正确,成功地构建了含有GPV主要结构蛋白基因的原核表达载体,为高效原核表达以及研制更为有效的基因工程疫苗打下了基础。  相似文献   

8.
根据猪链球菌2型的mrp基因自设计和合成了一对可扩增长度为885bp目的片段的引物,成功地建立了检测溶菌酶释放蛋白(MPR)的PCR方法,用XbaⅠ内切酶进行酶切,获得了与预期一致的578bp和307bp2的2个片段,并进行了PCR的特异性试验和敏感性试验。对马链球菌兽疫亚种、猪丹毒杆菌、猪肺疫巴氏杆菌和猪肺炎支原体的PCR检测结果均呈阴性;检测的敏感度可达100个细菌。另外,对9株从病猪体内分离的猪链球菌2型菌株进行检测了8个呈阳性;对15份正常屠宰猪扁桃体分离物的检测结果是1份为阳性。结果表明此法特异性敏感性均很高,可作为MRP快速诊和流行病学调查的手段。  相似文献   

9.
本研究旨在对绵羊NYD-SP27基因进行克隆和原核表达,并对其表达的蛋白进行生物信息学分析。根据GenBank中绵羊NYD-SP27基因序列(登录号:KX905090)设计1对特异性引物,通过PCR方法扩增目的基因片段,构建pET-22b(+)-NYDSP27重组质粒并转化E.coli DH5α感受态细胞,提质粒进行双酶切鉴定,将鉴定正确的pET-22b(+)-NYDSP27重组质粒转化E.coli BL21(DE3)感受态细胞,经IPTG诱导表达,对融合蛋白进行SDS-PAGE及Western blotting鉴定,并利用生物信息学方法对NYD-SP27基因编码的氨基酸序列进行分析。结果显示,试验成功扩增出大小为1 617 bp的NYD-SP27基因片段,并经NdeⅠ和Xho Ⅰ双酶切获得大小为5 400和1 617 bp的两条片段,表明成功构建了pET-22b(+)-NYDSP27重组质粒,诱导表达重组蛋白大小约60 ku,主要以包涵体的形式存在。NYD-SP27蛋白分子式为C2798H4319N737O819S19,原子总数为6 892,理论等电点(pI)为6.16,为酸性蛋白,不稳定系数为46.96,属于不稳定蛋白,总平均亲水性为-0.403。该蛋白无跨膜结构,无信号肽,含有45个潜在的磷酸化位点和24个抗原表位;NYD-SP27蛋白二级结构中的α-螺旋、β-折叠、延伸链和无规则卷曲分别占26.21%、3.90%、18.03%和51.86%。本试验结果可为深入研究绵羊NYD-SP27蛋白的作用机理提供理论依据。  相似文献   

10.
应用巢式聚合酶链反应(Nested PCR)-限制片段长度多态性 (restriction fragment length polymorphism, RFLP)方法对微小隐孢子虫(C.parvum)、安氏隐孢子虫(C.andersoni)和火鸡隐孢子虫(C.meleagrides)的鉴别进行了研究。结果显示C.parvum BOCC2、C.andesoni BOCC2和C.meleagrides CHCC1扩增产物片段大小分别为830bp、828bp和828bp,扩增产物分别经VspI酶切后形成3种不同的RFLP图谱,根据RFLP图谱可鉴别C.parvum、C.andersoni和C.meleagrides。本研究为我国隐孢子虫的分类和隐孢子虫病的分子流行病学研究打下了良好基础。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

13.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

14.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

15.
16.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

17.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

18.
19.
A knowledge of the microbiological status of milk and of the different structures in the mammary glands has great importance in elucidating the pathogenesis of mammary gland infections. The objective of this study was to evaluate the microbiological status of various structures in the mammary glands from naturally infected dairy cows following slaughter. A total of 94 samples of milk, 184 samples of mammary parenchyma, 168 samples of gland cisterns, and 168 samples of teat cisterns were collected for microbiological examination. Microorganisms were detected in 59.9% of all samples, 67.0% of the milk samples, 70.1% of the mammary parenchymas, 55.9% of the gland cisterns and 48.8% of the teat cistern samples. When all samples were considered, coagulase-negative Staphylococcus were the most prevalent (35.7%) followed by coagulase-positive Staphylococcus (12.2%), Corynebacterium bovis (2.4%), Prototheca sp. (1.9%), and Streptococcus dysgalactiae (1.5%). There was a significantly higher occurrence of microorganisms in the milk and mammary parenchyma compared to the gland cisterns and teat cisterns. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
Four grass plots were sequentially contaminated with goat faeces containing known numbers of unembryonated eggs of predominantly Haemonchus contortus and Trichostrongylus spp. between October 1982 and April 1983. Four other plots were similarly contaminated with sheep faeces between February and May 1987. An additional plot was repeatedly contaminated with sheep faeces from February to April 1987. Populations of free-living stages in faeces and of infective larvae (L3) in the herbage were subsequently monitored until the end of April and June of 1983 and 1987 respectively. During February and May 1987 two control cultures of sheep faeces were incubated in the laboratory at 25°C–30°C and at a constant temperature of 50°C and the free-living development was also monitored. L3 developed very readily in the faeces cultured at 25°C–30°C and in those spread on a grass plot in October, at the end of the wet season, but developed less on the plot contaminated in May at the start of the wet season. Worm eggs in faeces deposited on plots during the hot dry season (December to April) or incubated at 50°C died and disintegrated after 24–48 h exposure to the high environmental temperatures. The results indicate that it is unlikely that gastrointestinal nematodes of sheep and goats can develop or survive on open pasture during the dry season in the Nigerian derived savanna zone.  相似文献   

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